Conventional processes for making natural and processed cheese essentially utilize only casein. Generally only a few percent of whey proteins are incorporated into such cheeses since the majority of whey protein is retained in the whey and discarded as a by-product of conventional cheese-making processes. Whey proteins comprise about 14 to 24 weight percent of whole or skim milk's proteins and have a nutritional value at least comparable to that of casein. Therefore, the loss of whey proteins in conventional cheese making processes represents a costly inefficiency in these processes. The utilization of even a portion of whey proteins in the manufacture of natural and processed cheeses is of great commercial importance.
Therefore, attempts have been made to design processes which incorporate increased amounts of whey into these natural and process cheeses. However, processed cheese formulas with casein/whey protein ratios below about 3:1 give unacceptable textural characteristics (commonly expressed as “soft body”). Therefore, there remains a need for process cheeses with increased whey, which retain acceptable firmness, even with a casein to whey ratio of less than about 3:1.
Yee et al. (U.S. Pat. No. 5,750,177) describe natural cheeses with increased-whey protein having casein:whey ratios of 16:1 to 4:1 made from ultrafiltered cheese. The cheeses of Yee et al. require labor, time, and equipment-intensive ultrafiltered cheese, and result in cheese that has a whey protein:casein ratio that is no greater than that of the starting milk.
Czulak et al. (U.S. Pat. No. 4,518,616) describe methods for increasing the amount of whey protein incorporated into a natural cheese by ultra-filtering whey to form a whey protein concentrate, mixing the whey protein concentrate with milk to form an enriched milk, and then ultrafiltering the enriched milk, either before or after curding of the milk using lactic starter cultures, rennet, or combinations thereof.
The current invention provides formulations of process cheeses with casein/whey protein ratios below about 3:1 that retain a desirable firmness. The ratio of casein proteins to whey proteins in the process cheese of this invention preferably ranges from about 50:50 to about 75:25 (i.e., about 1:1 to about 3:1) as measured by gel electrophoresis. This provides major potential cost savings by allowing replacement of casein by whey proteins and/or supplementation of casein with whey proteins in a processed cheese product.